SCHG How-to:Guide

The SCHG How-to: series is a spinoff from the Sonic Community Hacking Guide with a focus on how-to, tutorials, and supplementary education. Whereas the traditional SCHG serves more as a map for users to navigate a ROM for themselves, the How-to series is more a "how to get from point A to point B" set of directions. Tutorials range from the very basic to very complex, with an eye towards making sure no part of the process is assumed or left out.

General How-Tos

• Work with Motorola 68000 assembly (by redhotsonic)
• Work with Objects (by Malevolence and MarkeyJester)
• Use a Hex Editor (by Scarred Sun)
• Edit Palettes Using Hex (by Scarred Sun)
• Use SonMapEd/Part 1 (by Chimpo)
• Use SonMapEd/Part 2 (by Chimpo)
• Import Art to SonED2 (by iojnekns)
• Set Up SonLVL (by MainMemory)

Game-Specific

Sonic 1

Fixing bugs

These guides describe the steps to take to fix bugs that are present in the original game or bugs that occur after altering something in the game.

• Fix the Hidden Points bug in Sonic 1 (by 1337Rooster)
• Display the Press Start Button text (by Quickman)
• Fix the SEGA Sound (by Puto)
• Fix the Level Select menu in Sonic 1 (by STHX)
• Fix the Walk-Jump Bug in Sonic 1 (by Cinossu)
• Fix demo playback (by FraGag)
• Fix a race condition with Pattern Load Cues (by FraGag)

Changing design choices

These guides describe how you can alter some behaviors in the game that might not be to your liking.

• Change Spike behavior in Sonic 1 (by FraGag)
• Fix the Special Stage jumping physics (by Mercury)
• Improve the fade in\fade out progression routines in Sonic 1 (by MarkeyJester)
• Fix scattered rings' underwater physics (by redhotsonic)

Adding features

These guides describe step-by-step how to add new features in the game. After following one of these guides, the feature should be fully functional in the game with no further work.

• Remove the Speed Cap (by Tweaker and Puto)
• Add Spin Dash to Sonic 1/Part 1 (by Lightning)
• Add Spin Dash to Sonic 1/Part 2 (by Puto)
• Add Spin Dash to Sonic 1/Part 3 (by shobiz)
• Add Spin Dash to Sonic 1/Part 4 (by Mercury)
• Port the REV01 Background Effects (by jman2050)
• Retain Rings Between Acts in Sonic 1 (by Afti)

Sound features

These guides cover the application of music and sound effects in the game. After following these guides, porting and adding original music should be possible.

• Expand the music index from $94 to $9F (by lukeusher123)
• Extend Music Slots in Sonic 1 (by Mikel)
• Play different songs on different acts (by nineko)
• Expand the music index to start at $00 instead of $80 (by HPZMan)
• Port Sonic 2 Final Sound Driver to Sonic 1 (by Kram1024)
• Port Sonic 3's Sound Driver to Sonic 1 (by Kram1024)

Extending the game

These guides will prepare you to introduce new content in the game. Merely following these guides will usually have no immediate effect in the game; you will need to provide custom content.

• Load chunks from ROM in Sonic 1 (by FraGag)
• Add Extra Characters (by Sonic 65)
• Make an Alternative Title Screen (by JcFerggy)
• Use Dynamic Tilesets in Sonic 1 (by HPZMan)
• Separate title art from GHZ/make GHZ load alternate art (by MKAmeX)
• Add a new zone in Sonic 1 (by FraGag)
• Set up the Goggle Monitor to work with it (by Selbi)
• Add new moves in Sonic 1 (by Ravenfreak)
• Add a Dynamic Collision system in Sonic 1 (by theocas)
• Extend the Sonic 1 sprite mappings and art limit (by MarkeyJester)
• Have a functional Eggman monitor in Sonic 1 (by nineko)
• Sonic 2 (Simon Wai Prototype) Level Select in Sonic 1 (by Kram1024)
• Enigma Credits in Sonic 1 (by Fukuller)

Miscellaneous

• Convert the Hivebrain 2005 disassembly to ASM68K (by Puto)

Qjimbo's Split Disassembly Guides

These guides were formerly hosted on The Glowing Bridge.

• Set up a Sonic 1 split disassembly (by Qjimbo)
• S1 Split Guides/Basic Level Editing (by Qjimbo)
• S1 Split Guides/Basic Art Editing (by Qjimbo)
• S1 Split Guides/Basic ASM Editing (Spin Dash) (by Qjimbo)

Sonic 2

Fixing bugs

• Fix demo playback (by FraGag)
• Fix a race condition with Pattern Load Cues (by FraGag)
• Fix bugs relating to Super Sonic (by MoDule)
• Use correct height when roll jumping (by MoDule)
• Fix jump height bug when exiting water (by MoDule)
• Fix Sonic 2's buggy spindash code and add spindash speeds (by GARY 'M 9)
• Fix screen boundary spindash bug (by Flamewing)
• Fix camera y position for Tails (by MoDule)
• Fix Tails' respawn speeds (by redhotsonic)
• Fix the EHZ Deformation bug (by qiuu)
• Fix bug in ARZ Boss arrow's platform behavior (by MoDule) (addition by redhotsonic)
• Fix HTZ's background scrolling mountains (by flamewing)
• Fix the OOZ launcher speed up glitch (by MoDule)
• Fix DEZ Eggrobo boss collision glitch (by flamewing)

Changing design choices

• Remove the Air Speed Cap (by Selbi and Puto)
• Enable/Disable Tails in certain levels (by Tamkis)
• Collide with water after being hurt (by MoDule)
• Improve the fade in\fade out progression routines in Sonic 2 (by MarkeyJester)
• Fix scattered rings' underwater physics (by redhotsonic)

Adding features

• Retain Rings when returning at a Star Post (by Mercury)
• Create Insta-kill and High Jump Monitors (by Tamkis)
• Create Clone and Special Stage Monitors (by Tamkis)

Extending the game

• Port Sonic 1's Sound Driver to Sonic 2 (by Tweaker)
• Port Sonic 3k's rings manager to Sonic 2 (by shobiz)
• Extend the level index past $10 in Sonic 2 (by kram)
• Extend the water tables in Sonic 2 (by Dani)
• Expand the music index to start at $00 instead of $80 (Sonic 2 Clone Driver version) (by Mikel, based on a guide by HPZMan)
• Add Extra Characters To Sonic 2 (By Manic Remix)

Miscellaneous

• Edit the Level Order in Sonic 2 with ASM‎ (by Malevolence and Metal_Man88)
• Alter the Ring Requirements in the Special Stages (by Mercury)
• Change the Special Stage characters to use normal DPLCs (by Flamewing)
• Speed up Ring Loss Process (w/ Underwater) (by redhotsonic)

Sonic 2 Master System

• Add Dynamic Palettes to Sonic 2 SMS (by Mikel)
• Relocate Player Object Logic in Sonic 2 SMS (by Glitch)
• Add a custom badnik to Sonic 2 SMS (by Glitch)
• Add a New Monitor in Sonic 2 SMS (by Ravenfreak)
• Add a Second Digit To the Lifecounter in Sonic 2 SMS (by Ravenfreak)
• How to Add new tiles in different acts in Sonic 2 SMS (by Ravenfreak)

Sonic 3 & Knuckles

• Work with Water in S3K (by Katelynn)
• Restore Sonic 2 Menus to Sonic 3 (by Mustapha)
• Fix Blue Knuckles (by Tamkis)
• Fix scattered rings' underwater physics (by redhotsonic)
• Fix Tails' respawn speeds (by redhotsonic)

Sonic Advance 3

• Switch Characters for Nonaggression (by Erik JS)

Sonic Adventure 1/DX

• Edit Sonic Adventure levels (by Polygon Jim)

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